i have ditched a creaking sir9 (bio-centric ebb) for an el mariachi (alternator dropouts). the salsa doesn't creak, its bliss. however it is heavier and feels a good bit stiffer, these things could make it better or worse for you, depending what you like. most of all i love it 'cos its QUIET! brilliant:-)

I didn't have a SIR9 but my last ride was a Reynolds 853 frame and I agree that the El Mariachi is considerably stiffer. I've seen the claimed weight on the SIR9 as 4.5lbs, while the El Mar is 5.3lbs in medium. Not sure if that Niner weight is accurate, but it would explain the difference in stiffness.

Alternator dropouts have been rock solid for me. A shop I was in the other day told me they've had no issues with them at all yet.

Also, if you're planning on getting a 2012 El Mar, you'll have the option of using a tapered fork.

El Mariachi Creaking Experience!
I am the proud owner of a 2011 El Mariachi, set up as a single speed with Salsa's steel 20mm thru maxle fork. I spent months putting this ride together with hand selected top shelf parts and during a very long succession of mistakes and discovery have encountered creaks that have forced me to dig deep into my shallow bag of patience and limited engineering knowledge to rectify. Briefly reading thru some of the others posts, I pridefully was laughing inside because I feel having spent hours dealing with my time of misery and befuddlement, I have finally become one with my stead. So forgive me for patting my own back here, but I just had to share these thoughts and hopefully the following will help fix your problems.
Illusions of grandeur- My dream of this bike was one of simplicity equals little if any mechanical problems and maintenance. MISTAKE NUMBER ONE!
The truth- the single speed configuration has its own set of complexities! The torque generated by this simple single speed set up imposes a lot of stress in both the rear drop out and bottom bracket region's and therefore slippage and creaks in these two regions are common. I felt after careful consideration and research that the alternator design was a superior design that addressed these issues and therefore not have them! MISTAKE NUMBER TWO.
Note: thus my issue is probably more inherent but I would think not isolated to the SS set up. I thought that for the longest time it was my bottom bracket that was the source until I one day decided to loosen the rear alternator drive side bracket and do my usual test of putting the front tire against a wall and with the non drive side crank in the 9 o'clock position pushing on it to torque the frame and test to hear if I could generate my annoying creak and this time it solved the problem and bam boom bang, I found THE SOURCE!

The good news- everyone seems to be in the same boat! In others words you didn't make mistake buying the El Mariachi! I for one am hopeful that I have stumbled upon the solution for my problems and feel confident that the alternator design is perhaps one of the best design's out there and am very happy that I chose this bike over a EBB bottom bracket designed bike!!!!
Proof- my good friend has a 2012 Sir Nine and hasn't remedied his creak issues generated in the EBB(I hope I'll eat my words on this and that Niner's newly designed EBB fixes his problem). I think I have found a solution! though in it's infancy test wise has given me at the least new hope. This after trying everything INCLUDING THROUGH BOLTING THE BRACKET THUS ENABLING ME TO TORQUE THE HELL OUT OF THE BRACKET (THIS MADE THE NOISE EVEN WORSE!).
SOLUTION- try making a gasket out of Stans No Tubes rim tape and putting it between the bracket and the alternator drop out. So far this has stopped the creaking!!!!! Though time will tell. ( at least I know the source of the creak- half the battle)
In addition- Through this process I have trouble shot every possible source including lubing spokes. I would suggest that you face the head tube because Salsa fails to do so from the factory. I would also race and face the BB. And while your at it spray a rust inhibitor inside your frame (can't hurt, only helps). Good Luck and may the force be with you!

Can't think of a single negative. I sold off some pretty spendy plastic and aluminum bikes after getting my El Mar...
I just got a Casseroll for a song, but want another El Mariachi to set up as a single speed.

Been running a 2010 Bomb Pop Blue and have had absolutely no issues with creaking or anything else. Single speed with WB Rock Solid fork. Buy one, you'll at least like it a lot! My only con is, mine does'nt have the 44mm head tube, and I don't work for a Salsa Dealer anymore.

I'm using the same 2010 Bomb Pop El Mariachi in a single speed set up. So I am intrigued that you have not had any Creaks what so ever. It has been a real issue for me so I wonder if something may be wrong with my frame. I have tried everything to tame this problem aside from changing out components ie. - Hub etc. Can you get more specific with what your build is. I'm running a Hope ss rear hub with WTB i23 rims using Continental 2.2 race Kings. the front hub is a Hadley 20mm thru maxle linked to salsa's Grande steel maxle fork which I love but I did on my last run notice a lot of for and aft flex when I got on the bikes on a steep down hill street the other day! I'm using a race face Turbine crank and Turbine BB. The chainring is a Renthal ultra light 32 and the rear cog is a Chris King 20t stainless. the chain is a KMC single speed 3/32 chain. seat post is a Thompson masterpiece pared with a WTB saddle. Brakes are Avid BB7 pared with Shimano ice tech 180mm rotors front and rear. stem is a 80mm thompson 4x pared with crank bros 3- 28.5 wide handle bar(aluminum). Brake levers are shimano XT's. Any ideas on taming the creak issue are welcome although my test thus far with the gaskets between the alternator dropouts and frame seem to be working. Lastly do you experience any kind of rotational knocking from your cranks and I'm talking a barely noticeable and minute knocking sensation? thank for taking the time!

I'm using the same 2010 Bomb Pop El Mariachi in a single speed set up. So I am intrigued that you have not had any Creaks what so ever. It has been a real issue for me so I wonder if something may be wrong with my frame. I have tried everything to tame this problem aside from changing out components ie. - Hub etc. Can you get more specific with what your build is. I'm running a Hope ss rear hub with WTB i23 rims using Continental 2.2 race Kings. the front hub is a Hadley 20mm thru maxle linked to salsa's Grande steel maxle fork which I love but I did on my last run notice a lot of for and aft flex when I got on the bikes on a steep down hill street the other day! I'm using a race face Turbine crank and Turbine BB. The chainring is a Renthal ultra light 32 and the rear cog is a Chris King 20t stainless. the chain is a KMC single speed 3/32 chain. seat post is a Thompson masterpiece pared with a WTB saddle. Brakes are Avid BB7 pared with Shimano ice tech 180mm rotors front and rear. stem is a 80mm thompson 4x pared with crank bros 3- 28.5 wide handle bar(aluminum). Brake levers are shimano XT's. Any ideas on taming the creak issue are welcome although my test thus far with the gaskets between the alternator dropouts and frame seem to be working. Lastly do you experience any kind of rotational knocking from your cranks and I'm talking a barely noticeable and minute knocking sensation? thank for taking the time!

I ran the same 2010 El Mar for nearly 2 years as a SS. Never had any creaking issues.

I crashed hard enough on my Tallboy to break my leg,
The carbon is way more durable than most people.

I bought one of the limited 2013 ss, and first its a pain in the Arse to find one. But it has been worth every penny I spent on it. My ride before was a 2012 fisher sawyer, such a big difference. I had sooooo many problems with my sawyer when it was set up as a ss. But for one thing, riding that has made me a stronger rider, cause the Marc is sooooooo much lighter. Its at 24.6lbs and thats with all AL except the bars. The only other thing I would change is the fork to a nice carbon. I have been thinking about a niner (orange to go with the setup) or maybe a white brothers. Either way this bike is faster, stiffer, and it has brought a smile to my face when I climb these days. How many NON carbon bikes can make you say that?

I have enjoyed my El Mariachi, though it has taken a season of riding to fully appreciate it. I also experienced some creaks early on but the LBS fixed that. My only complaint is the tiny triangle for a frame bag.

i'm riding a 2012 el mar. only creaks have come from the headset (still haven't figured that out) and the crap stock GXP BB. the versatility of the alternators and oversize head tube was definitely a selling point.

however, i have had some rust from under the top tube gusset. the LBS cleaned it out and treated it with frame saver, but there's still a very small amount of rust appearing. i've since sealed it with clear nail polish to try and stop any more moisture from getting in there. just something to be aware of.

the ride is compliant as you'd expect. however, it's not the stiffest frame in the world, especially in the rear triangle. there's some flex, but it's nothing crazy. tire clearance is pretty good back there; i could fit 2.4 mountain kings with the dropouts only a few millimeters short of all the way forward.

with the dropouts all the way back it's a really stable feeling, both climbing and descending. with them all the way in, the bike feels a lot quicker and more nimble.

Thats interesting about the rust...I noticed that my slate blue El Mar has the same brown spot under the gusset, but I thought it was dirt. I'll have to check that out tonight.

The only parts I broke on mine was the rear hub bearings and BB. Rear hub bearings went out twice on me until I finally solved that by going to a Flow/Hope wheelset. The BB is letting the cranks move side to side, so I'm gonna upgrade that to a Hope BB pretty soon. Overall, the bike has been very good to me!

since i needed a new BB anyway, i snagged an X9 crankset from jenson for $110. totally changed the feel of the bike with the stiffer cranks (compared to the low-end sram cranks that came stock). a worthy upgrade.

During my ever evolving progression to eliminate my menacing creek issue I have abandoned the gasket fix between the alternator dropouts and started lubing the DT swiss competition spokes (black), after that failed to work last night I took a bottle of lube with me on my ride and after a series of stop and lubes to remedy the worsening creek finally tried tightening the rear QR and wa la creak was virtually eliminated. If this is the culprit and I hope it is because after a agonizing year of this I am totally gun shy, I will be the happiest El Mariachi owner ever! eventually I'll post pic's but I wanted to get this thing perfect first only then could i feel good about boasting every component with recommendations. Creeks are a ***** but if I solve this I will be able to say short of a cracked frame or design flaw it can be fixed!

P.S. thanks for all the reply's even though they were completely unhelpful.

I have had my 2012 El Mar for 1 year now and love it. I bought the frame only and built it up myself. I have had it set-up both SS and 1x9 and love it either way. I did have an issue with the alternators when I broke the derailuer hanger and I stripped the bolts on them (my bad) when trying to set it up SS on the trail... But Salsa sent me a new set for free... I have never had any creaks or squeaks and have had a Reba on it since day 1. I am a larger rider at 280 lbs and this bike has been great...

I like it so much I just ordered a Salsa 2012 Horsethief on clearance via Universal Cycles for my trails/mountain geared bike and ordered the rigid fork for the EL Mar which will be set up as my full time SS rigid fun bike.